Pesachim 50b
פסחים נ׳ ב — ד"ה בְּנֵי בַיְישָׁן נְהוּג דְּלָא הֲווֹ אָזְלִין
Pesachim 50b:11
The passage distinguishes between different communities’ practices and explicitly addresses variation in religious custom, a foundational source for assessing when divergent practice is legitimate rather than a contradiction in law.
בְּנֵי בַיְישָׁן נְהוּג דְּלָא הֲווֹ אָזְלִין מִצּוֹר לְצִידוֹן בְּמַעֲלֵי שַׁבְּתָא. אֲתוֹ בְּנַיְיהוּ קַמֵּיהּ דְּרַבִּי יוֹחָנָן, אָמְרוּ לוֹ: אֲבָהָתִין אֶפְשָׁר לְהוּ, אֲנַן לָא אֶפְשָׁר לַן. אֲמַר לְהוּ: כְּבָר קִיבְּלוּ אֲבוֹתֵיכֶם עֲלֵיהֶם, שֶׁנֶּאֱמַר: ״שְׁמַע בְּנִי מוּסַר אָבִיךָ וְאַל תִּטּוֹשׁ תּוֹרַת אִמֶּךָ״. בְּנֵי חוֹזָאֵי נָהֲגִי דְּמַפְרְשִׁי חַלָּה מֵאָרוֹזָא, אֲתוֹ וַאֲמַרוּ לֵיהּ לְרַב יוֹסֵף. אֲמַר לְהוּ: נֵיכְלַהּ זָר בְּאַפַּיְיהוּ. אֵיתִיבֵיהּ אַבָּיֵי: דְּבָרִים הַמּוּתָּרִים וַאֲחֵרִים נָהֲגוּ בָּהֶן אִיסּוּר —
As the mishna discusses the requirement to observe local customs, the Gemara relates: The residents of Beit She’an were accustomed not to travel from Tyre to market day in Sidon on Shabbat eve. In deference to Shabbat, they adopted a stringency and would not interrupt their Shabbat preparations even for a short sea voyage. Their children came before Rabbi Yoḥanan to request that he repeal this custom. They said to him: Due to their wealth, it was possible for our fathers to earn a living without traveling to the market on Friday; however, it is not possible for us to do so. He said to them: Your fathers already accepted this virtuous custom upon themselves, and it remains in effect for you, as it is stated: “My son, hear your father’s rebuke and do not abandon your mother’s teaching” (Proverbs 1:8). In addition to adhering to one’s father’s rebuke, i.e., halakha, one is also required to preserve his mother’s teaching, i.e., ancestral customs. The Gemara relates additional customs: The residents of the city of Ḥozai were accustomed to separate ḥalla from rice dough. They came and told Rav Yosef about this custom. He said to them: Let a non-priest eat this dough in their presence to show them unequivocally that this custom has no legal basis. Abaye raised an objection to him: With regard to matters that are permitted, but others were accustomed to treat them as a prohibition,
